The invention concerns a winding device for a sheet of paper or cardborad. Such a device is known from DE 3,221,929 C3. Such so-called double-carrier-roll winding devices have the disadvantage that prior to reaching the maximum size, disruptive spots or even breaks can occur in the winding construction due to the high linear compression of the sheet winding. It is also difficult, in the case of very large winding diameters, to maintain constant the support pressure over the entire winding length. In the case of support roll machines, windings are conducted in two tension pins. In this way, it is possible to take up an arbitrary portion of the roll weight by unloading devices and to reduce correspondingly the pressure of the winding. These devices, however, are very expensive.
The task of the invention is to create a winding device, in which two support elements are constructed or arranged in such a way that the linear pressure on the sheet winding remains relatively small, so that comparatively large diameters of the winding can be obtained.
This task is resolved according to the invention by a winding device having at least two support elements that extend over the length of the sheet, one support element being a carrier roll and the other including a rigid carrier for guiding the sheet; a sheath arranged around the carrier; a carrying shoe connected to the carrier for hydrodynamically reacting with the sheath; a concave pressure surface adapted to mate with the carrying shoe and having a radius of curvature that essentially corresponds to a maximum winding of the sheet, whereby the carrying shoe is adapted to be continually positioned at the periphery of the sheet.
In fact, pressure devices with rolls or roll-type pressure elements are known, in which one of the pressing elements is a so-called tubular roll (see U.S. Pat. No. 4,563,245). Thus, one of the pressing elements is a tube-shaped surrounding sheath pressed by a pressing shoe, whereby sheath and pressing shoe are held by a rigid, often tube-shaped carrier. According to the invention, however, it was recognized that the latter can be used for pressing fixtures on a device known in and of itself, but with the corresponding changes in order to reduce the linear pressure of the winding.
Therefore, advantageously, one proceeds by adapting the pressing shoe to the respective position or to the size of the winding in order to consistently provide a sufficient guidance and support of the latter.
Thus one can proceed once by shifting the pressing shoe preferably called the carrying shoe) along a circumferential path, whereby the carrying shoe is rigidly bound with a carrier-particularly of cylinder form, which is then rotated around its longitudinal axis in order to turn the carrying shoe to the necessary position. The carrying shoe can also be arranged in a turning manner on a central carrier, which can be configured also in a hollow cylindrical shape. Hydraulic piston cylinder units can then serve as lifting elements. It is also possible to provide flexible pressure tubing between the carrier and the carrying shoe. This has the advantage that it supports the carrying shoe over its entire length. In order to prevent a sagging of the latter, the shoe can be formed thinner than if piston rods were engaged on its ends.